Pneumatic squeeze head with pressure supply booster means



Oct. 17, 1967 E. K. HATCH ETAL 3,347,307

PNEUMATIC SQUEEZE HEAD WITH PRESSURE SUPPLY BOOSTER MEANS Original FiledDec. 11, 1961 e Sheets-Sheet 1 FIG I INVENTOR EDMOND K. HATCH 8 BY LEONF MILLER WWO" ATTORNEYS Oct. 17, 1967 E. K. HATCH ETAL 3,347,307-

PNEUMATIC SQUEEZE HEAD WITH PRESSURE SUPPLY BOOSTER MEANS 6 Sheets-Sheet2 Original Filed Dec. 11, 1961 ZNVENTOR. EDMOND K. HATCH 8| BY LEON F.MILLER FIG 2 ATTORNEYS 6 Sheets-Sheet 5 I EDMOND K HATCH 8 LEON F MILLERATTORNEYS t- 1957 E. K. HATCH ETAL PNEUMATIC SQUEEZE HEAD WITH PRESSURESUPPLY BOOSTER MEANS Original Filed Dec. 11, 1961 Oct. 17, 1967 E. K.HATCH ETAL 3,347,307

PNEUMATIC SQUEEZE HEAD WITH PRESSURE SUPPLY BOO STER MEANS v 6Shets-Sheet 4 Original Filed Dec. 11, 1961 FIG 5 INVENTQR. FIG l2'EDMOND K, HKI'CH a BY LEON F. MILLER 76 I 546M I ATTORNEYS Oct. 17,1967 E. K. HATCH ETAL 3,347,307.

PNEUMATIC SQUEEZE HEAD WITH PRESSURE SUPPLY BOOSTER MEANS Original FiledDec. 11, 1961 6 Sheets-Sheet 5 INVENTOR EDMOND K HATCH 8 BY LEON FMLLERM, Mya" fiamly ATTORNEYS Oct. 1 7, 196 I E. K. HATCH ETA L 3,3

PNEUMATIC SQUEEZE HEAD WITH PRESSURE S UPPLY BOOSTER MEANS OriginalFiled Dec. 11, 1961 6 Sheets-Sheet 6 228 -i 229 20' 2o 209 -2o2 FIG 9INVENTOR LEON DF KMIEIEEQ a FIG BY ATTORNEYS United States Patent3,347,307 PNEUMATIC SQUEEZE HEAD WITH PRESSURE SUPPLY BOOSTER MEANSEdmond K. Hatch, Brecksville, and Leon F. Miller, Rocky River, Ohio,assignors to The Osborn Manufacturing Company, Cleveland, Ohio, acorporation of Ohio Original application Dec. 11, 1961, Ser. No.158,499, now Patent No. 3,234,601, dated Feb. 15, 1966. Divided and thisapplication Dec. 7, 1965, Ser. No. 512,066

3 Claims. (Cl. 164-173) This invention relates generally, as indicated,to a molding machine with a universal squeeze board and moreparticularly to a highly versatile foundry molding machine capable ofproducing rapidly a variety of high quality foundry sand molds. Thisapplication is a division of application Serial No. 158,499, filedDecember 11, 1961, entitled Molding Machine With Universal SqueezeBoard, now Patent No. 3,234,601.

The present invention represents certain improvements in moldingmachines of the overhead squeeze type as, for example, the machinedisclosed in our copending application, Serial No. 133,700, filed August24, 1961, entitled Overhead Squeeze Molding Machine, now Patent No.3,169,285. In such application, there is disclosed a foundry moldingmachine wherein only the squeeze head as opposed to the squeeze ram isshuttled into and out of operative position. Such machine alsoincorporates an optional jolt action in an extremely fast cycle ofoperation.

With the machine of the present invention, a multiple piston squeezehead is employed wherein each of the pistons is manifolded to apneumatic pressure system wherein a line pressure of, for example, 80pounds per square inch can be boosted to as high as 400 pounds persquare inch so that the optional jolt action can largely be dispensedwith even for such molds as cylinder block molds. Also, such multiplepiston squeeze head can be employed with large flasks to produce largemolds and a uniform pressure can be obtained on such molds regardless ofthe pattern contour. Even with such complex molds as cylinder blockmolds, a uniform hardness is obtained. The machine of the presentinvention also employs a unique overhead draw mechanism which willquickly facilitate the drawing of the pattern from the mold and thedischarge of the finished mold from the machine.

It is therefore an important object of the present invention to providea versatile foundry molding machine which will apply a uniform highpressure to a variety of foundry sand molds regardless of patterncontour.

A further important object is the provision of a squeeze head for suchfoundry molding machines using a pneumatic pressure system wherein theline pressure can readily be boosted to and maintained at a preselectedhigh pressure.

Other objects and advantages of the present invention will becomeapparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention,then, comprises the features hereinafter fully described andparticularly pointed out in the claims, the following description andthe annexed drawings setting forth in detail certain illustrativeembodiments of the invention, these being indicative, however, of but3,347,307 Patented Oct. 17, 1967 a few of the various ways in which theprinciple of the invention may be employed.

In said annexed drawings:

FIG. 1 is a side elevation of a machine in accordance with the presentinvention;

FIG. 2 is an end elevation of such machine as seen from the right inFIG. 1 on a somewhat enlarged scale;

FIG. 3 is an enlarged side elevation" partially broken away of theoverhead draw mechanism;

FIG. 4 is a side elevation of such draw mechanism partially broken awayand in section;

FIG. 5 is an enlarged fragmentary side elevation illustrating theshuttling sand measuring box and the flask latching and feed mechanisms;

FIG. 6 is an end elevation of such mechanism of FIG. 5 as seen from theright thereof;

FIG. 7 is an enlarged top plan view of the jolt table of the presentinvention;

FIG. 8 is a vertical section of such table taken substantially on theline 8-8 of FIG. 7;

FIG. 9 is a fragmentary end elevation of an alternative form of patternchange mechanism that may be employed with the machine of the presentinvention;

FIG. 10 is a fragmentary horizontal section illustrating such patternchange mechanism;

FIG. 11 is a fragmentary side elevation of such pattern changemechanism;

FIG. 12 is a diagrammatic illustration of the pneumatic booster whichmay be employed with a squeeze head of the present invention; and

FIG. 13 is a similar diagram showing the booster in its alternateposition.

Referring now to the annexed drawings and more particularly to FIGS. 1and 2, the machine embodiment of the present invention illustratedherein comprises a base I mounted on a floor 2 with the base havingbolted thereto as shown upstanding inverted 'U-shape side frames 4 and5. Each side frame includes legs 6 and 7 and an arch top 8. The arch topportions 8 of each of the side frames 4 and 5 support therebetween anarch-like crosshead 9 of suitable welded plate framing as shown moreclearly in FIG. 2. The crosshead 9 supports relatively largepiston-cylinder asemblies 10 and 11, such pistoncylinder assemblieshaving relatively large diameter rods which are connected through boots12 and 13 respectively to a vertically movable squeeze head supportingframe 14. Also mounted on the crosshead 9 is a somewhat smallercentrally disposed piston-cylinder assembly 16 used primarily forelevating the head, the relatively small rod of which is connectedthrough boot 17 to the head 14. Guide rods 18 and 19 extending upwardlyfrom the frame 14 pass through guide bushings 20 mounted on each end ofthe crosshead 9.

A sand fill chute or hopper 22 is also mounted on the head of themachine by means of brackets 23 as shown in FIG. 1. Molding sand may befed into such hopper from any convenient overhead system such as a beltconveyor, not shown. Whereas the hopper 22 is held stationary, a sandmeasuring box 24 is mounted for horizontal longitudinal shuttlingmovement on a conveyor illustrated generally at 25. The bottom of thesand measuring box 24 is provided with louvers; 26 mounted on verticallyadjustable frame 27, such louvers being operated from an open to closedposition and vice versa by piston-cylinder assembly 28. The sandmeasuring box 24 is mounted on a carriage frame 29 which includes a topcut-01f plate 30, such frame being provided with transversely extendingflange 31 which supports the frame including the measuring box on therollers 32. The rollers 32 are mounted on the insides of a pair of rails33 which are secured to the inside of the legs 6 of each of the sideframes 4 and by suitable brackets. The rail 33 and rollers 32 form onesection of the discontinuous conveyor 25, the opposite end section beingformed by rails 34 and rollers 35 similarly mounted by means of brackets36 on the insides of the legs 7 of the frame members 4 and 5.

The center section of the conveyor is comprised of rails 37 havinginwardly directed rollers 38 thereon which are mounted on the distalends of pairs of U-shape side members 39 which are secured to the headframe 14 for vertical movement therewith. (Note FIG. 2.) It can now beseen that the conveyor 25 is discontinuous with the center sectioncomposed of the rails 37 and rollers 38 being carried for up and downmovement with the squeeze head by the large vertical squeeze pistons ofthe pistoncylinder assemblies and 11.

A squeeze head 40 which, in the illustrated embodiment, comprises aplurality of downwardly extending pistons 41 of piston-cylinderassemblies 42 is provided with pairs of side flanges 43 and 44, whichform outwardly directed channels enclosing the rollers of the conveyor25. The squeeze head 40 is connected to the sand box 24 by means of anupwardly directed U-shape member 45 on the head 40 which engages a pin46 on the box 24 so that when the head and box are horizontally aligned,they will be locked together for movement along the conveyor 25 as aunit. Such movement is obtained by piston-cylinder assemblies 48 and 49,the rods of which are pin connected to brackets on the end of the sandmeasuring box carriage as indicated at 50. The cylinders are pivotallyconnected as shown at 51 to brackets 52 secured to the legs 6 of theside frame members 4 and 5.

The sand box 24 and squeeze head 40 when horizontally aligned are thuslatched together for movement as a unit by the action of thepiston-cylinder assemblies 48 and 49 and such are alternately placed oneor the other over a centrally disposed jolt table and piston as semblyindicated at 55. Such assembly includes a jolt table 56, which is shownin more detail in FIGS. 7 and 8, supporting a pattern plate 57containing a pattern 58.

Flasks F are shuttled into the machine on a roller conveyor 60 whichlike the conveyor 25 is discontinuous. The conveyor 60 extends beneaththe conveyor 25 and parallel thereto longitudinally of the machine andis comprised of a first section which includes rails 61 having inwardlydirected rollers 62 thereon which engage beneath the side flanges 63 and64 of the flasks F as seen more clearly in FIG. 2. The rails 61 mayextend between the legs 6 of the side frames 4 and 5 and externalsupport means generally indicated at 65 in FIG. 1. The center section ofthe conveyor 68 is comprised of rails 66 having inwardly directedrollers 67 thereon, such rails being mounted for vertical movement onpairs of brackets 68 (note FIGS. 3 and 4) which are connected to therods of draw piston-cylinder assemblies 69 and 70 at the top of themachine as will hereinafter be described. The conveyor rails 66 like theconveyor rails 37 are thus vertically movable. The conveyor 60 iscompleted by a discharge section comprised of rails 71 having inwardlydirected rollers 72 mounted thereon, such rails being secured bybrackets or the like to the insides of the legs 7 of the side framemembers 4 and 5. The rails 37 of the conveyor 25 as well as the rails 66of the conveyor 60 are positioned in the center of the machinevertically aligned with the table 56 and the pattern 58 positionedthereon. It will be understood that the conveyor 60 may be only a smallportion of a complete flask and mold handling system. The flask F maythen be moved into the machine on conveyor 60 to be positioned on therails 66 to be lowered by the draw piston-cylinder assemblies 69 andonto the periphery of the pattern plate 57 which is clamped to the table56.

Referring now to FIGS. 5 and 6, it will be seen that the carriage frame29 for the sand box 24 which, it will be recalled, is mounted forhorizontal shuttling movement on the conveyor 25 by means of thepiston-cylinder assemblies 48 and 49, includes depending bracket members75 which have mounted on the bottom ends thereof a strike-01f plate 76.Such brackets 75 also pivotally support flask latching members indicatedgenerally at 77 and 78 which include hook portions 79 (note FIG. 5)which engage over the top peripheral leading edge of the flask as shownat 80. The latch members 77 and 78 are interconnected by a shaft 82. Theproximal ends of the latch members 77 and 78 are provided withvertically extending elongated slots 83 which receive pins 84 and 85passing through upstanding ears on brackets 86 and 87 (note FIG. 6).Adjustable stop screws 88 and 89 engage the tops of the latch members tolimit the counterclockwise pivotal movement thereof as viewed in FIG. 5.The latch members are operated by a piston-cylinder-assembly 90, the rod91 of which is connected to the latch member 77. Such piston-cylinderassembly may, for example, be a relatively small assembly having a 2 /2inch bore with a 2%. inch stroke and cushioned at both ends. Extensionof such piston-cylinder assembly will pivot the latch members in thecounterclockwise direction about the pins 84 and 85 to engage the topperipheral edge of the leading end of the flask F and when suchpiston-cylinder assembly is extended, the flask will be latched formovement With the carriage 29 in a position vertically aligned with thesand box 24. The blind end of the piston-cylinder assembly is pivoted asindicated at 92 to one of the vertical brackets 75.

The carriage 29 may also be employed to move a flask into position whereit can be engaged by the latch members 77 and 78. This is accomplishedby the latch member 95 having bifurcated tip 96 which, like the latchmembers 77 and 78 engages the leading top edge of the flask. The latchmember 95 is pivoted at 97 to 2. depending bracket 98 and includes anarm 99, the distal end of which is pivoted at 100 to the rod 101 ofpiston-cylinder assembly 102 which is mounted beneath the carriage frame29. Thus retraction of the piston-cylinder assembly 102 and the rod 101will pivot the arm 99 and the latch member 95 in a counterclockwisedirection as viewed in FIG. 5 so that the bifurcated tip will bevertically clear of the top edge of the flask. When extended, thebifurcated tip will engage the flask edge and the flask F will thus belocked for movement with the carriage 30. Latch members 104 pivoted tothe rails 61 as at are provided with a bottom sloping cam surface 106which engages and rides over the top flange 107 of such flasks and dropsbehind such flanges when the flask is in the right-hand position shownin FIG. 5 so that the flask will be held in vertical alignment beneaththe sand box 24 to be engaged by latch members 77 and 78.

Thus as the carriage 29 is moved by the piston-cylinder assemblies 48and 49, the leading flask F will be positioned on the rollers o-f rails66 aligned with the pattern 57. The rails 66 are then lowered to..placethe flask F on the pattern by means of the draw piston-cylinderassemblies 69 and 70. Such lowering of the rails and flasks supportedthereby will then automatically disengage the flask from the latchmembers 77 and 78. Retraction of the pistoncylinder assembly 90 as wellas the retraction of the piston-cylinder assembly 102 will release bothlatch mechanisms and as the carriage 29 is returned to its originalposition, the latch members 77 and 78 will now be in position to engagethe leading top edge of the next succeeding flask when thepiston-cylinder assembly 90 is extended. Similarly, the latch member 95will be in position to engage the next succeeding flask F again to latchtwo flasks for movement in tandem with the carriage 29. A hold downroller 108 may be employed to assist in securing the flask F in positionvertically beneath the sand box 24.

Referring now more particularly to FIGS. 3 and 4, it will be seen thatthe rails 66 forming the center section of the conveyor 60 are mountedfor vertical uniform movement by means of the draw piston-cylinderassemblies 69 and 70, the rods 110 of which are each connected to to asquaring shaft 111 by means of the linkage 112 shown more clearly inFIG. 3. One end of the link 112 is pin connected to a clamp 113 on therod 110 and the other end is pin connected to arm 114 which is keyed toshaft 111. A similar arm and linkage will connect the opposite end ofthe shaft 111 to piston-cylinder assembly 70. Since the draw mechanismsfor each side of the machine operated by the respective piston-cylinderassemblies 69 and 70 will be allochirally identical in form, only thedraw mechanisms for the piston-cylinder assembly 69 will be described indetail. The lower end of the rod 110 is provided with a threaded portion114 having a stop nut 115 thereon which will engage plate 116 in theuppermost position of the rod 110. Accordingly, the nut 115 may beemployed as an adjustment to obtain the proper height of rail 66 in theuppermost position. The distal end of the rod 110 is provided with areduced diameter threaded portion 117 and nuts 118 and 119 may beemployed to clamp such rod to the top web 120 of a guide frame 121. Theguide frame 121 is comprised of two cylindrical bushing members 122 and123 which slide along vertically extending guide rods 124 and 125respectively. Such guide rods are secured as by screws 126 incylindrical receptacles 127 and 12-8 welded or otherwise rigidlyfastened to the bottom of the arch or top portion 8 of the side frame 4.The lower ends of the guide rods 124 and 125 are secured in a crossframe member 139 extending between the legs 6 and 7 of the sideframemember 4. This cross frame member may be of the welded plateconfiguration shown more clearly in FIG. 4. A stop bolt 131 may besecured in a bottom web 132 in the guide frame 123 and the engagement ofthis :bolt with an upstanding projection 133 on the frame 130 willgovern the bottom or lower extent of movement of the rod 110.

The brackets 68 for the conveyor rails are secured to each of thebushing members 122 and 123 and adjusting screws 135 may be employed toadjust the vertical height of the brackets with respect to the bushingmembers. The brackets are provided with inturned bottom edges 136 whichsupport the rails 66 thereon. Such brackets also mount verticallyextending cushioning dashpot assemblies 137, the rods 138 of which inthe retracted position are beneath the top level of the rollers 67. Inthe extended po. sition, the rods serve to lift the flask slightly offthe rollers 67. Such brackets also support a small horizontal axispiston-cylinder assembly 140, the capped piston-rod end of which, whenin the extended position, engages against the flask flange 63 during thedrawing operation to stabilize the flask and to keep the flask fromrolling after the flask is drawn and to keep it from rolling when firstlowered onto the pattern prior to the molding operation. It is notedthat in the illustrated embodiment, four pistoncylinder assemblies ordashpots 137 are employed for each rail 66, the outer ones beingsupported on brackets 141.

Now with special reference to FIGS. 1, 2 .and 4, it will be noted thatthe extent of vertical movement of the draw rails 66 and rollers 67mounted thereon and accordingly the flask F is shown in such figures at142. In such lower position, the flask will be then transferredvertically downwardly from the conveyor 60 to rest upon the top of thepattern plate 57 which together with the flask and pattern 58 forms acompleted mold box. Extension of the squeeze piston-cylinder assembliesand 11 will lower the head frame 14 and thus the squeeze head 40 toposition the rods 41 and cylinders 42 in the phantom line position shownat 143 in FIG. 2 with the feet or squeeze biscuits B of the piston rodswell within the peripheral top of the flask now positioned on thepattern plate. As seen in FIG. 4, the U-shape side frames 39 will movedownwardly to approximately the phantom line position indicated at 144.

Referring now to FIGS. 7 and 8, it will be seen that the table 56includes a central depending piston which fits within cylinder 151 whichis provided with a top flange 152 bolted to shoulder 153 of adaptor 154.The adaptor is, in turn, bolted to the base 1 as indicated at 155. Thebottom of the cylinder 156 may be provided with an inlet indicateddiagrammatically at 157 so that air under pres sure can be admitted tothe bottom of the piston 150 which will elevate the piston and thus thetable 56. An exhaust port 158 may be provided with a shut-ofl valve 159which will normally be opened to permit the jolt operation. Air underconsiderable pressure will be admitted to the bottom of the piston toraise the piston and the table until the exhaust port is clear at whichtime the air behind the piston will be exhausted permitting the table todrop providing the jolt action. Guide rods 160 and 161 provided atdiametrically opposite corners of the table extend through bushingsindicated at 162 to keep the table from rotating about its central axis.Such guide rods may be provided with stops 163 limiting the uppermovement of the table and it will be understood that safety exhaustports may also be provided. The jolt piston is generally conventionaland may be employed' optionally in the cycle of the machine.

The top of the table 56 is provided with two diametri cally oppositecylinders 165 and 166, each being provided with a piston shown at 167.The rods 168 of such pistons are pivoted to a clevis 169 which is inturn pivoted at 170 to a clamping member 171, such clamping member beingpin connected at 172 to lugs 173 and 174 on the edge of the table 56.The top end of the pivotally mounted clamp 171 is provided with a fingeror tip portion 175 which engages over a bottom flange 176 on the pattern57. T-shape passage 177 provides an inlet port for the blind ends of thecylinders 165 and 166 and passages 178 and 179 provide air pressureinlet ports for the rod ends of such cylinders. Exhaust port 180 isprovided for each of the cylinders through the top as indicated. Thuseach of the piston-cylinder assemblies in the table 56 is doubleactingso that the clamp members 171 can quickly be pivoted to and from patternplate clamping position so that such patterns can readily be removedfrom and secured to such table.

To facilitate such pattern changes, the machine embodiment of FIG. 1 isprovided with two transversely extending shafts and 186 which aresupported for rotation in bearings 187 and 188 at each end thereof. Theshafts are positioned at each side of the table 56 and each such shafthas mounted thereon two arms 189 and 194) supporting rails 191 and 192having a series of hori- Zontally aligned rollers 193 and 194 thereon.These respective rails and rollers form a pattern change conveyor whichcan be spread apart by pivoting oppositely the arms about the axes ofthe shafts 185 and 186. Suitable stops may be provided to maintain thearms and conveyor sections in the position shown in FIG. 1, for example.When it is desired to change the pattern, the shut-off valve 159 may beclosed and this then closes the jolt exhaust port and admission of airunder pressure to the blind end of the cylinder will elevate the tableand thus the pattern plate and pattern. When the pattern plate issufliciently elevated, the rollers 193 and 194 may be manually pushedinwardly or toward each other to fixed stops. The clamping pistons 167in the table 56 will now be retracted to release the clamps 171. In thisposition, the rollers will be beneath side flanges 196 and 197 on thepattern plate and when air has been exhausted from beneath the joltpiston by opening valve 159, for example, the pattern plate will restupon the rollers and further lowering of the table will release the pinand bushing connection between the table and pattern plate. A newpattern may then be shuttled into place and the procedure reversed.

In FIGS. 9 to 11, there is shown an embodiment of the invention whereina more automatic pattern change is employed. Such machine may comprise,for example, a base 200 with columns 201, 202, 203 and 204 being thelegs of the arch-like side frames which support the crosshead in thesame manner as in FIGS. 1 and 2. The base is centrally provided with thejolt and elevating table 205 which may be identical in form to the tabledisclosed in FIGS. 7 and 8. The machine, itself, may be substantiallyidentical in form and operation to the machine disclosed in FIGS. 1 and2. In this machine, however, a pattern change frame is provided whichincludes side rails 208 and 209 each having a plurality of rollers 210and 211 thereon which project inwardly and support a plurality ofpatterns indicated diagrammatically at 212, 213 and 214. The patterns212 through 214, like the pattern plate in the FIG. 1 embodiment, areprovided with top side flanges indicated at 215 and 216 in FIG. 9 bywhich the patterns are supported on the rails for movement therealong.The frame also includes a transverse plate 217 and a pivot shaft 218 atopposite ends thereof, the plate being supported on a frame 219 which ispivotally connected at 220 to the rod of vertically extendingpiston-cylinder assembly 221. The shaft 218 may be pivoted in pillowblocks 223 and 224 which are mounted on stand 225 positioned adjacentthe machine frame. Similarly, the piston-cylinder assembly 221 may bemounted in a stand 226 positioned at the other side of the machineframe.

Mounted on brackets 228 and 229 on the rails 208 and 209 are long strokepiston-cylinder assemblies 230 and 231. The rods of thesepiston-cylinder assemblies are connected by links 232 and 233 to guiderods 234 and 235 respectively. Each guide rod is mounted in bushings 236and 237 secured by brackets to the respective rails. Latch members 240and 241 may be secured to such guide rods for movement therewith as bythe set screws or the like shown in FIG. 10. Such latch members includelugs 242 and 243 engaging cooperating lugs on the ends of, for example,the patterns 213 and 214 respectively. Accordingly, extension of therods of the piston-cylinder assemblies 230 and 231 will move thepatterns 213 and 214 as a unit along the rails 208 and 209 when thepiston-cylinder assembly has been extended to pivot the entire frameabout the axis of pivot shaft 218 to elevate, for example, the pattern213 to disconnect the pin-bushing connection between the pattern and thetable. When the piston-cylinder assembly 221 is retracted, the selectedpattern will be engaged with the pin-bushing connection in the table andthe patterns on either sides thereof will be engaged by adjustablescrews 244 and 245 in the stand 225 and such screws 246 and 247 in thestand 226. These screws serve to elevate the patterns from the rollers210 and 211 on the rails when the frame is in its lowermost position andthis precludes the patterns from rolling from their elected positionsduring the cycle of operation of the machine. It should be here notedthat with such automatic pattern shuttle, the machine is able to operateto change patterns for every cycle. It will be understood that the rails208 and 209 can be continuations of additional conveyor systems so thatpro-selected patterns may be placed in order and fed to the machine tobe automatically positioned by the pattern shuttle mechanism abovedescribed so that a variety of molds can be made continuously on thesame machine by careful programming. In the illustrated embodiments, thedirection of pattern travel will be normal to the direction of flask andhead travel.

Referring now to FIGS. 12 and 13, it will be seen that the universalmultiple piston-squeeze head shown diagrammatically at 40 is providedwith a manifold 250 so that the blind end of each of the downwardlyextending cylinders 42 are connected to a common source of air pressure.

Air is supplied to the squeeze head from a normal plant line pressuresupply indicated at 251 which may, for example, be at approximatelypounds per square inch. Air will be supplied from such source through aconventional pressure regulator R to pass through a check valve 252 intoa small booster cylinder 253. Air at such regulated pressure also entersa branch line 254 to pass into a conventional pilot operated three-Waydirectional valve 255. The inlet port for such valve is shown at 256 andthe exhaust port is shown at 257. As seen in FIG. 12, the directionalvalve in the position shown connects the branch line 254 with a line 258leading to the bottom of a large booster cylinder 259. The booster thancomprises the two different size cylinder chambers 253 and 259interconnected by a double piston ram 260. Small button valves 261 and262 in the booster operate to relieve the air pressure from the pilots263 and 264. When the piston 260 moves to the down position, buttonvalve 262 will relieve top pilot 263 through line 265, the bottom pilot264 of the valve 255 being under pressure. The relieving of pilot 264 isaccomplished through pilot line 266. With the valve in the up position,line 254 is connected to line 258 and continued pressure acting on thelarger area of the bottom piston of ram 260 in cylinder 259 of thebooster causes the booster ram to rise and force air within the cylinderchamber 253 out passage 268 through check valve 269 into the manifold250. As the ram 260 rises, it will engage the button valve 261 relievingpilot line 266 causing the spool 270 of the directional valve to shiftto the FIG. 13 position now venting the chamber 259 through the line 258and the exhaust port 257. Air then passing from source 251 through thecheck valve 252 into the chamber 253 behind piston 271 will force thebooster ram down. Continued oscillation of the booster ram up and downwill increase the air pressure in the manifold from, for example, 80pounds per square inch to over 400 pounds per square inch and when thedesired pressure has been reached, the booster will then stall. Thepoint at which the booster stalls will be determined by two factors,viz, the setting of valve R and the difference in area of the twopistons of ram 260. Any leakage in the piston-cylinder assemblies 42 orin the manifold will cause the pressure in the manifold to drop and thebooster again to operate until the loss of pressure is restored. Severalstrokes of the booster ram up and down may be required to increase themanifold pressure to the desired point.

Variable pressures may be obtained on the sand by adjusting the pressurein the system for the overhead squeeze pistons 10 and 11 which force thehead down into engagement with the sand in the mold box. It will beunderstood that the squeeze biscuits or feet B may vary in size, spacingand shape so that barred flasks, for example, may be accommodated. Inany event, the head being separately mounted on the conveyor 25 mayeasily be disconnected from the carriage frame 29 for replacement orrepair purposes. The line 268 may be connected to the manifold as shownat 272 in FIG. 2.

With continued reference to FIG. 2, it will be seen that stop plates 273and 2'74 may be provided accurately to position the head 40 within theframe 14 and a swingable latch 274 at the opposite end of frame 14 maybe provided automatically to swing into position about the pivot 275 asthe head is lowered automatically to latch the head 40 in the propervertically aligned position. A spring 276 connected to a stanchion 277may be employed automatically to swing the latch into proper latchingposition as the head is lowered. When the head is raised, the latchingmember will be caused to engage an abutment on the frame to swing clearto the position shown in FIG. 2 so that the head may then be replaced bythe sand box by means of the piston-cylinder assemblies 48 and 49.

The universal squeeze head 40 which rides into and out of the frame 14with the shuttle of the sand box comprises a multiplicity of downwardlyprojecting pistons having feet B on the lower or distal ends thereofwhich engage the sand as the piston-cylinder assemblies and 11 areextended to lower the frame and thus the head into sand engagement. Thepistons 41 which are backed by a manifolded air pressure system are thenable to adjust relative to each other transferring squeeze pressure fromone cylinder to another although the pressure in each cylinder willremain equalized so that each foot engaging the sand will exert the sameamount of pressure on the sand within the flask.

OPERATION Referring now mainly to FIGS. 1 and 2, it will be seen thatthe louvered sand measuring box 24 in the position shown will receiveloose flutty sand falling from the hopper 22. Beneath the box 24 on theconveyor 60 a flask F has been engaged by the latches 77 and 78 as seenin FIG. 6 to he in effect locked for movement with the box 24. Apreceding flask P will also be latched for movement with the box by thelatch member 95. With the squeeze head 40 and the squeeze head frame 14in up position and also the draw piston-cylinders 69 and 70 in the upposition and further with the jolt table down and a selected patternclamped thereon, fluid pressure is now applied to the blind ends of thelarge horizontal shuttling cylinders 48 and 49 which laterally shift thesand box 24 and the head 40 to bring the sand box over the pattern andto shift the head out onto the extended end of the conveyor 25 formed bythe rails 34. Movement of the sand box in this manner brings a cut-offplate 30 into position beneath the hopper 22. This shuttling movement ofthe box and head also brings a flask into the proper position and if amold has been made on the previous cycle, it would also simultaneouslypush out the completed mold on the extended section 71 of the conveyor60 as shown at 280.

As soon as the flask has been brought into position over the pattern,the draw piston-cylinder assemblies 69 and 70 are energized by suitablelimit switches, for example, to move the rails 66 downwardly which nowsup: port the flask and place such flask on the pattern plate. Whendown, the mold box is then assembled and the louvered box opens todischarge the sand charge onto the pattern in the flask. At this point,at the option of the operator, the jolting can begin and simultaneouslythe latch member 95 will release the next flask to be engaged by thelatch memebrs 77 and 78, now in their raised position due to retractionof piston-cylinder assembly 90, and the retraction of thepiston-cylinder assemblies 48 and 49 will return the sand box 24 to itsoriginal position and replace the sand box over the flask with theuniversal squeeze head 40. With the louvers closed, the sand measuringbox 24 is now in position to be refilled. Surplus sand will be struckfrom the mold box by the strike-01f plate 76 as the sand box isreturned. The latch member 95 will now be pivoted in a clockwisedirection to engage the next preceding flask.

At the completion of the jolt cycle, the large overhead squeezecylinders 10 and 11 are now supplied through valves 281 and 282 with oilunder high pressure to lower the frame 14 and the universal squeezehead. Oil may also be supplied to the blind end of piston-cylinder 16 toincrease the squeeze pressure. When the head 40 is brought into positionin the frame 14, the plate 273 will engage the frame properly to centerthe head and the latch 274 will pivot into position as the head startsto lower locking the head in the properly centered position in the frame14. The booster shown in FIGS. 12 and 13 has previously been set tocreate and maintain a high pressure in all of the relatively smallpiston-cylinder assemblies 42 and as the feet or squeeze biscuits B onthe rods 41 engage the sand and begin to compress the air within themanifolded system, the fluid is then increased in pressure and eachpiston will move upwardly or retreat according to the resistance itencounters. In this: manner, a desired equalization takes place so thateach squeeze biscuit will exert the same pressure on the sand. The fluidsupply system for the piston-cylinder assemblies 10 and 11 may beprovided with a pressure responsive mechanism so that when the desiredpressure is reached, the head is raised. Since the piston-cylinderassemblies 10 and 11 are provided with relatively large rods, the rodends of the pistons therein have a relatively small area and the smallerpiston-cylinder assembly 16 can be employed to assist in raisin-grapidly the head 40 and the frame 14. When the head is raised, thevalves 281 and 282 will be opened fully to exhaust rapidly the fluidfrom the tops of the piston-cylinder assemblies 10 and 11. Immediatelyfollowing the raising of the head, the draw piston-cylinder assemblies69 and 70 will be retracted to raise the flask and the thus formed sandmold stripping the mold from the pattern. The small horizontal cylinderswill press in on the flask flange to keep it steady during the drawingoperation.

As soon as the mold has been stripped from the pattern, the patternshuttle mechanism shown more clearly in FIGS. 9 through 11 may beemployed to change patterns. After the pattern has been unclamped by thepistoncylinder assemblies shown more clearly in FIGS. 7 and 8, thepiston-cylinder assembly 221 may be extended to pivot the frame to liftthe patern 213 clear of the pinbushing connection with the table. Whenthe pattern is clear, the piston-cylinder assemblies 231 and 232 may beemployed to shuttle into operative position the next pattern. Whenproperly positioned, the piston-cylinder assembly 221 is retracted andthe pistons in the table are extended firmly to latch the selectedpattern in place. With the embodiment shown in FIG. 1, the rails 191 and192 may manually or automatically be pushed into position after thepattern has been unlatched and the jolt table 56 raised so that theflanges 196 and 197 will overlie the rollers 193 and 194 when thuspositioned. With the new pattern in position, the machine is then readyto commence the next cycle of operation.

With the present construction, not only are the squeeze piston-cylinderassemblies 10 and 11 on top of the machine away from the sand and dirt,but also the draw piston-cylinder assemblies 69 and 70. Moreover, thesquaring shaft linkages for the draw pistons are enclosed within theside frame top portions 8.

It can now be seen that there is provided a highly versatile foundrymolding machine which will quickly produce a variety of molds includinglarge molds with large flasks squeezing the sand therein to a uniformhardness.

Other modes of applying the principles of the invention may be employed,change being made as regards the details described, provided thefeatures stated in any of the following claims or the equivalent of suchbe employed.

We, therefore, particularly point out and distinctly claim as ourinvention:

1. A squeeze head for foundry molding machines comprising a plurality ofresiliently cooperatively movable sand engaging pneumatic squeezemembers, manifold means interconnecting said pneumatic squeeze membersoperative to maintain the sand squeeze pressure exerted by each memberthe same, and air pressure booster means operative to control andmaintain the degree of such sand squeeze pressure exerted by saidmembers as a whole, said booster means comprising a ram having twopistons of difierent area, and valve control means for said boostermeans operative to reciprocate said ram to pump air into said manifoldmeans.

2. A squeeze head as set forth in claim 1 wherein said valve controlmeans comprises a pilot operated three-way valve, said pilot operatedvalve being controlled by re- 11 ciprocation of said ram to bring thepressure in said manifold to a predetermined degree.

3. A squeeze head as set forth in claim 2 including means responsive toa deficiency in the pressure in said manifold means to commenceoperation of said booster means and to the attainment of suchpredetermined pressure to halt operation of said booster means.

References Cited UNITED STATES PATENTS 2,351,872 6/1944 Parker 60-545 12Lytle 60-52 Stur'gis 60-52 Taccone 164171 Hatch et a1 164-196 Hatch eta1. 164-173 Hatch et a1 164-173 Ellms 164212 J. SPENCER OVERHOLSER,Primary Examiner.

R. D. BALDWIN, Assistant Examiner.

1. A SQUEEZE HEAD FOR FOUNDRY MOLDING MACHINES COMPRISING A PLURALITY OFRESILIENTLY COOPERATIVELY MOVABLE SAND ENGAGING PNEUMATIC SQUEEZEMEMBERS, MANIFOLD MEANS INTERCONNECTING SAID PNEUMATIC SQUEEZE MEMBERSOPERATIVE TO MAINTAIN THE SAND SQUEEZE PRESSURE EXERTED BY EACH MEMBERTHE SAME, AND AIR PRESSURE BOOSTER MEANS OPERATIVE TO CONTROL ANDMAINTAIN THE DEGREE OF SUCH SAND SQUEEZE PRESSURE EXERTED BY SAIDMEMBERS AS A WHOLE, SAID BOOSTER MEANS COMPRISING A RAM HAVING TWOPISTONS